Propeller.



No. 868,220. PATENTED OCT. 15, 1907. J. PORTELLI & J. D. CHAPMAN.

PROPELLER.

APPLICATION FILED APRA. 1907.

gmpevxlfow J RFEHJZ J. BER k Witnesses UNITE s'ra rns PATENE onrrcn.

JULIAN PORTELLI AND JOSEPH D. CHAPMAN, OF LOS ANGELES, CALIFORNIA.

PROPELLER.

Specification of Letters Patent.

Patented Oct. 15, 1907.

Application filed April 4, 1907. Serial No. 366,420-

To all 'u'hom it may concern:

Be it-known that we, .TUIJIAN PORTELLI and Josnrn D. CHAPMAN, citizensof the United States, residing at Los Angeles, in the county of LosAngeles and State of (.alifornia, have invented certain new and usefulImprovements in Propellers: and we do hereby declare the following to bea full, clear, and exact description of the invention, such as willenable others skilled in the art to which it appertains to make and usesame, reference being had to the accompanying drawings, and to theletters and figures of reference marked thereon, which form a part ofthis specification.

This invention relates to new and useful improve ments in propellers,and the object in view is to produce a simple and etlicieut device ofthis character whereby the greatest amount of power may be obtained at aminimum expense, and consists in pro pcller comprising various detailsof construction and arrangements of parts which will be hereinafterfully described and then specifically detined in the appended claims.

Our invention is illustrated in the accompanying drawings, in which:

Figure I is a. side elevation of the propeller, and Fig. 2 is a rear endview.

Reference now being had to the details of the drawings by letter, Adesignates. a shaft or stem of the propeller and B designates a singleplate of metal having two wings B. Said plate is fastened at itslongitudinalcenter to the end of the shaft or stem, and the portions oftlicfplate on either side of its point of connection with said shaft arecurved in opposite directions, and the wings, designated by letters B,are bent spiral shaped. with their forward ends secured to the stem orshaft at points diametrically opposite.

I In operation, when it desired-to drive a boat equipp d with ourpropeller forward, the shaft is rotated in the direction indicated byarrows in Fig. 1 of the drawings, which will cause the spiral wings ofthe plate to cut into the water and exert a pushing force thereon,thereby causing the propeller to exert a pushing force upon the boat towhich it is attached. A reverse movement to the propeller will cause acorresponding pulling force in the opposite direction, there byaffording means whereby a boat equipped with our improved propeller maybe moved backward. the provision of a plurality of propellers, one uponeither side of the keel of-a boat, and so arranged that one propellermay be driven in one direction while the other is driven in a reversedirection, means will be afforded whereby a boat may be turned aroundwithin a short compass or be readily guided.

While we have described our invention as being applicable especially tobeats, it will be understood that the same may be utilized as a currentwheel by which great power may be transmitted, the power increasing withthe swiftncss of the current, and if desired, the invention may beapplied to wind-mills, in which the force of the wind may be exertedupon the wings of the plate.

What we claim is 1. A propeller comprising a shaft, a plate fixed at itslongitudinal center to said shaft, said plate being bent laterally inopposite directions and having forwardly ex tending spiral wings, theends of which are fastened to said shaft, as set forth.

2. A propeller comprising a shaft, a plate fixed at its longitudinalcenter to one end of the shaft and having,- op positely extending curvedportions with tapering and spiral wings curved in opposite directionsand fastened at their forward ends to said shaft. as set forth.

2'. A propeller comprising a shaft, a single plate provided with anaperture to receive said shaft, a shoulder upon the latter, a nutadapted to hold the plate at its longitudinal center against saidshoulder, said plate having laterally projecting curved portions withtapering spiral wings, and a collar fixed to the shaft and engaging theforward ends of said wings, as set fortlr In testimony whereof wehereunto aflix our signatures in the presence of two witnesses.

his

JULIAN X PORTELLI.

mark JOSEPH D. CHAPMAN. Witnesses DAVID ALLEN, WILLARD H. CLARK.

